The growing popularity of this transparent gem with shades ranging from blue to purple has been driven by its vivid color, high clarity and its potential to be cut into various, large shapes.
Tanzanite may be a relative newcomer to the world of colored stones, but it was one of the most exciting jewelry discoveries of the 20th century.
It quickly became the second most popular blue gemstone after sapphire.
Not only is it a lucky stone for those born in December, it’s also the 24th wedding anniversary jewel.
Mined commercially in one place, tanzanite is rarer than diamonds.
Tanzanite origins and legends
Tanzanite has a single source: the Merelani hills of northern Tanzania.
The Merelani Hills of northern Tanzania is the only place on earth where tanzanite is mined commercially. Grass-covered hills, scrub, rocky soil and occasional trees form the local landscape. In mechanized mining operations, workers retrieve tanzanite from mines dug more than 100 meters deep into the earth. To the north of the mines, the snow-capped slopes of Mount Kilimanjaro rise.
By chance, in 1967, a Masai tribesman discovered a cluster of intensely transparent crystals, ranging in color from purple to blue, emerging from the earth. He tipped off a local gem finder, who hoped it was a new sapphire deposit. Instead, the deposit contained one of the world’s newest gemstones: tanzanite.
Before long, further tanzanite discoveries followed in that nearly 20-square-mile area. No one knew for sure what those beautiful crystals were, but everyone wanted to claim the profits from the mining. The new stone would come to be known as tanzanite and would compete in popularity with the three coloured gemstones at the top of the pyramid: sapphire, emerald and ruby.
Tiffany & Co recognized its potential as an international retailer and struck a deal, becoming its main distributor. Tiffany & Co named the jewelry in honor of Tanzania and promoted it with a major advertising campaign in 1968. Almost overnight, tanzanite became popular with leading jewelry designers as well as with customers who had an eye for beauty and unusual gemstones.
Technical characteristics of tanzanite
Tanzanite is a violet blue to bluish purple variety of the mineral zoisite.
Tanzanite’s appearance is greatly influenced by its pleochroism, which is the ability of a gemstone to show different colors when viewed in different directions.
Tanzanite’s pleochroism was documented in scientific papers shortly after its discovery. In 1969, an American mineralogist described the jewel’s pleochroic colors as “red-violet, deep blue and yellow green”.
Today, most gemstones are heat-treated, which eliminates or reduces the yellow-green or brownish pleochroic color, maximizing the blues and purples.
High-quality Tanzanite can be violet blue – similar to a fine sapphire color – or a single, predominantly violet hue. Some stones may also appear more purplish, depending on how the cutter chooses to polish the stone.
The exact color depends on the inherent color of the original rough stone, its size, the pleochroic colors the cutter favors when orienting the shaped stone, and the light under which the finished gem is viewed.
Cool lighting – like fluorescence equivalent to daylight – will emphasize the blue of the tanzanite, while warm lighting – like incandescence – will make it appear more purple. Like other coloured gemstones, vivid, brightly coloured tanzanites are highly sought after. Lighter pastel shades are more abundant and affordable than vivid colors.
Tanzanite is resistant to the effects of normal heat, light and ordinary chemicals. However, this stone can crack if exposed to very high temperatures or sudden changes in temperature and degrades easily. It can be attacked by hydrochloric and hydrofluoric acid.
Mineral class: zoisite
Chemical formula: Ca2Al3(SiO4)3OH
Colour: purple, sapphire-blue, red-brown, violet, yellowish-green
Specific gravity: 3,2 – 3,4
Gloss: glassy, matt
Mohs hardness: 6,5-7
Tanzanite price stability
The price history for tanzanite has seen many sharp increases and decreases over time. These price changes have been linked to the limited number of mines and the limited geographical location of the world’s tanzanite resource. Tanzanian government decisions and regulations, can have an immediate impact on the availability and price of the entire world supply.
Tanzanite lacks the price protection enjoyed by most stones, which are mined in several countries and on different continents. Events such as floods or mining challenges also have an immediate impact on supply and price.
Energetic and spiritual properties
Tanzanite is said to strengthen the immune system, detoxify the blood and improve vitality. It helps regenerate cells, skin, hair and protects against the side effects of medical or surgical interventions.
Tanzanite is useful in treating psychological disorders, stress and nervous tension. It can relieve headaches and together with other treatments, such as counselling, can help cure chronic alcoholism.
Tanzanite helps to overcome experiences of fear and crisis and rebuild confidence. It helps to resolve questions about the meaning of life and to come to terms with oneself.
Tanzanit has powerful spiritual energies that can connect your mind to the higher realms.
As a stone at work, tanzanite is calming and soothing. Even a small piece is beneficial for overcoming communication difficulties. It is also practical in providing a solution to problems when it seems like there is none. It is a good stone for career change.
Worn in jewelry, tanzanite not only stays in the gold field and brings one’s consciousness into a permanently higher state, but brings positive self-awakening qualities to others who see its beauty.
Tanzanite stone care tips
The combination of warm water and soap is the best way to clean this stone. Ultrasonic and steam cleaners are never recommended for tanzanite. Prolonged contact with water and detergents should be avoided, as exposure will result in loss of lustre.